Instrument for use in navigation.



APPLIOATION FILED 111N119, 1910.

Patented Apr. 4, 1911.

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ATTORNEYS direction.

UNITED "STATES OVE nnnmnnn snnnnns, or KEY wns'r, rnonrna.

. INSTRUMENT FOR USE IN NAVIGATION. v

Specification of Letters Patent.

Patented Apr. 4, 1911.

Application filed June 9, 1910. Serial No. 565,966 1 To all whom it may cmwem:

Be it known that I, Ovn B. SANDERS, a subject of the King of Norway, and a resident of Key West, in the county of Monroe and State of Florida, have invented a new and Improved Instrument for Use in Navigation, of which the following is a full, clear, and exact. description.

This invention relates to a new and improved instrument for use navigation, whereby the true course is determined from the'compass course in the shortest possible space of time, by mechanically allowing for the deviation and variation.

An objectof this invention is to provide a device which will be simple invconstruction,

inexpensive to manufacture, strong, durable,

readlly accessible, and easily operated.

, A further object of this invention is to provide an instrument with a plurality of relatively adjustable circular graduations whereby the various *deviationsand variations may be. allowed for. v

These and further objects, together with the construction and combination of parts, will be more fully described hereinafter, and specifically set forth in the claims.

Reference may be had to the accompanying drawings, formin a part of this specifi cation, in which s at characters of reference indicate corresponding parts in both the views, and in which- Figure 1 is a to plan vlew of the instrument; and Fig. 21s a vertical section on the line 22 of Fig. 1.

Referring more articularly to the separate parts of the evice, 1 indicatesa base which is preferably supported by legs 2, preferably three in num r so as to form a positive support. Secured to the base 1 .there is provided a plate 3, which is preferably stationar and immovable relative to the base 1, an is provided on its upper-sur face with divisions indicating the oints of compass such as'N., E., S., and representln north, east, south and west, with interme 'ate points indicated thereon. This plate 3 is also provided adjacent its periphe cry with a graduated circular scale mdicat ing more accurately the various degrees,

north and south points, and ascend to ninety degrees at the east and west points in each Rotatably mounted on the base'l there is pnoy ided a ring 4, which also has inscribed 'on its upper surface a circular graduated scale indicating in degrees angles from zero graduated scale is arranged in close juxtaposition to the scale on the plate.

to ninety degrees in each quadrant. This Concentric with the plate 3. and the ring 4 I there is provided an annular member 5, wh1ch is rotatably mounted on the base I,

and is also rotatable relative to the ring 4.'

This annular member 5 is likewise provided with a graduated circular scale similar to the scales on the ring 4 and the plate. 3, and measuring in degrees angles from zero to ninety degrees in each quadrant.

For the purpose of reading three angles in radial alinement there is provided. a pointer 6, which is secured to a spindle 7 rotatably .the plate 3, and the base 1. The pointer 6 and the-spindle 7 are adapted to be rotated by a suitable thumb screw 8, so as to swing the1 pointer over the face of the various sea es.

For the purpose of manipulatin the ring 25 westerly, then the true course will be south 95 east,'or north 85 east. In place of making the necessary subtractions and annular member 5, as illustrated inFig. 1, is set ten points easterly of the zero of the scale on the ring 4,'thus'correcting for the ber 5 are then moved 25 westerly that is to say, the zero on the scale on the ring 4 is ofiset westerly125 relative to the vzero on the plate.3. The inter 6 is then set at south 80 east to in 'cate the com ass course. The magnetic course can then directly read 'as south 70 east on the scale on the ring 4, and the true coursewill be directly readable on the scale on the plate 3 as north 85 east.- The three readings are brought into 'alinement by means of the inter" 6, after the deviation and variation I ve been ple and readily operatedmeans for almost mounted in a centrally located opening in p15 4, it is provided with an interna gear or rack 9, which is engaged by-a pinion 10 on then be south 70 east. -I the variation is additions, the zero of the .scale on the outer allowed for. It will thus-be seen that a Simdeviation. The ring 4 and the annular meminstantaneously obtaining the true course from the compass course, when the deviation and variation are known, is provided.

While I have shown one embodiment of my invention, I do not wish to be limited to the specific details thereof, but desire to be protected in the various changes, alterations and modifications which I may make within the scope of the appended claims.

Having thus described my invention I claim as new and desire to secure by Letters Patent;

l. The combination with a base, of a circular plate secured to said base, and having a circular scale on its outer periphery, indicating degrees from zero to ninety degrees, starting from opposite ends of a diameter of said plate, and extending to the right and left in both directions to the ends of a diameter located at right angles to said firstmentioned diameter, an annular member having a scale thereon, rotatably mounted on said base, and a ring having a scale thereon rotatably mounted on said base, said scale on said ring being arranged in juxtaposition to said scales on said annular member and said plate.

2. The combination with a base, of a circular plate secured to said base, and having a circular scale on its outer periphery, indicating degrees from zero to ninety degrees, starting from opposite ends of a diameter of said plate, and extending to the right and left in both directions to the ends of a diameter located at right angles to said first mentioned diameter, an annular member having a scale thereon, rotatably mounted on said base, a ring having a scale thereon rotatably mounted on said base, said scale on said ring being arranged in juxtaposition to said scales on said annular member and said plate, and means for rotating said rm 3% The combination with a base, of a cir cular plate secured to said base, and having a circular scale on its outer periphery, indicating degrees from zero to ninety degrees, starting from opposite ends of a diameter of said plate, and extending to the right and left in both directions to the ends of a diameter located at right, angles to said first-mentioned diameter, an annular member having a scale thereon, rotatably mounted on said base, a ring having a scale thereon rotatably mounted on said base, said scale on said ring being arranged in juxtaposition to said scales on said annular member and said plate, said ring having an internal annular rack thereon, a gear rotatably mounted on said base engaging said rack, and means for operating said gear.

at. The combination with a base, of a three-point support for said base, a plate connected to said base and having a circular scale thereon, a ring rotatably mounted on said base and having a circular scale arranged in juxtaposition to said first-mentioned scale, an annular member rotatably mounted on said base and having a scale arranged in juxtaposition to said second-men'- tioned scale, means for manipulating said ring relative to said plate, and said annular member, and a pointer rotatably mounted on said base and adapted to indicate alined graduations on said scales.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

UVE BERNI-IARD SANDERS.

Witnesses:

N. N. HEssE BENNY JENSEN. 

